The endocannabinoid system consists of the cannabinoid (CB) receptors, CB(1) and CB(2), the endogenous ligands anandamide (AEA, arachidonoylethanolamide) and 2-arachidonoylglycerol (2-AG), and their synthetic and metabolic machinery. The use of cannabis has been described in classical and recent literature for the treatment of pain, but the potential for psychotropic effects as a result of the activation of central CB(1) receptors places a limitation upon its use. There are, however, a number of modern approaches being undertaken to circumvent this problem, and this review represents a concise summary of these approaches, with a particular emphasis upon CB(2) receptor agonists. Selective CB(2) agonists and peripherally restricted CB(1) or CB(1)/CB(2) dual agonists are being developed for the treatment of inflammatory and neuropathic pain, as they demonstrate efficacy in a range of pain models. CB(2) receptors were originally described as being restricted to cells of immune origin, but there is evidence for their expression in human primary sensory neurons, and increased levels of CB(2) receptors reported in human peripheral nerves have been seen after injury, particularly in painful neuromas. CB(2) receptor agonists produce antinociceptive effects in models of inflammatory and nociceptive pain, and in some cases these effects involve activation of the opioid system. In addition, CB receptor agonists enhance the effect of mu-opioid receptor agonists in a variety of models of analgesia, and combinations of cannabinoids and opioids may produce synergistic effects. Antinociceptive effects of compounds blocking the metabolism of anandamide have been reported, particularly in models of inflammatory pain. There is also evidence that such compounds increase the analgesic effect of non-steroidal anti-inflammatory drugs (NSAIDs), raising the possibility that a combination of suitable agents could, by reducing the NSAID dose needed, provide an efficacious treatment strategy, while minimizing the potential for NSAID-induced gastrointestinal and cardiovascular disturbances. Other potential "partners" for endocannabinoid modulatory agents include alpha(2)-adrenoceptor modulators, peroxisome proliferator-activated receptor alpha agonists and TRPV1 antagonists. An extension of the polypharmacological approach is to combine the desired pharmacological properties of the treatment within a single molecule. Hopefully, these approaches will yield novel analgesics that do not produce the psychotropic effects that limit the medicinal use of cannabis.

Mucoadhesive drug therapy destined for localized drug treatment is gaining increasing importance in today's drug development. Chitosan, due to its known biodegradability, bioadhesiveness and excellent safety profile offers means to improve mucosal drug therapy. We have used chitosan as mucoadhesive polymer to develop liposomes able to ensure prolonged residence time at vaginal site. Two types of mucoadhesive liposomes, namely the chitosan-coated liposomes and chitosan-containing liposomes, where chitosan is both embedded and surface-available, were made of soy phosphatidylcholine with entrapped fluorescence markers of two molecular weights, FITC-dextran 4000 and 20,000, respectively. Both liposomal types were characterized for their size distribution, zeta potential, entrapment efficiency and the in vitro release profile, and compared to plain liposomes. The proof of chitosan being both surface-available as well as embedded into the liposomes in the chitosan-containing liposomes was found. The capability of the surface-available chitosan to interact with the model porcine mucin was confirmed for both chitosan-containing and chitosan-coated liposomes implying potential mucoadhesive behavior. Chitosan-containing liposomes were shown to be superior in respect to the simplicity of preparation, FITC-dextran load, mucoadhesiveness and in vitro release and are expected to ensure prolonged residence time on the vaginal mucosa providing localized sustained release of entrapped model substances.

The role of socioeconomic status in hip fracture incidence is unclear. In a diverse population of elderly, higher education was found to be associated with lower, whereas living alone, compared to being married/cohabiting, with higher hip fracture risk. Educational level and marital status may contribute to hip fracture risk.

INTRODUCTION: The evidence on the association between socioeconomic status and hip fracture incidence is limited and inconsistent. We investigated the potential association of education and marital status with hip fracture incidence in older individuals from Europe and USA.

METHODS: A total of 155,940 participants (79 % women) aged 60 years and older from seven cohorts were followed up accumulating 6456 incident hip fractures. Information on education and marital status was harmonized across cohorts. Hip fractures were ascertained through telephone interviews/questionnaires or through record linkage with registries. Associations were assessed through Cox proportional hazard regression adjusting for several factors. Summary estimates were derived using random effects models.

CONCLUSIONS: The combined data from >150,000 individuals 60 years and older suggest that higher education may contribute to lower hip fracture risk. Furthermore, this risk may be higher among individuals living alone, especially among the age group 60-69 years, when compared to those being married/cohabiting.

To study acute tolerance, rats were anesthetized with interrupted i.v. allopregnanolone infusions where the "silent second" in the electroencephalogram (EEG) was the target. Animals were killed either directly at the first silent second or at the silent second level after 30 or 90 min of anaesthesia. Acute tolerance was demonstrated at 90 min of anaesthesia as earlier shown. In situ hybridization showed a decreased expression of the gamma-aminobutyric acid(A) (GABA(A)) receptor subunit alpha4mRNA amount in the thalamus ventral-posteriomedial nucleus of the tolerant rats. A parallel change in the abundance of the alpha4 subunit was detected with immunohistochemistry. The increase in maintenance dose rate (MDR) was significantly negatively correlated with the alpha4mRNA in the thalamus ventral-posteriomedial nucleus, and positively correlated with alpha2mRNA in different hippocampal subregions. There was also a positive relationship between the alpha1mRNA amounts in the different hippocampal subregions, with significant differences between groups. These changes in GABA(A) receptor subunits mRNA expression and protein (alpha4) might be of importance for the development of acute tolerance to allopregnanolone.

The endogenous cannabinoids anandamide (arachidonoyl ethanolamide, AEA) and 2-arachidonoyl glycerol (2-AG) exert their effect by activating cannabinoid receptors (CB). These receptors mediate a broad range of physiological functions such as beneficial effects in pain and inflammation, although little is known about the expression of CB receptors in human pain conditions. AEA and 2-AG are short- lived molecules due to their rapid cellular accumulation and metabolism. The enzymes primarily responsible for their degradation are fatty acid amide hydrolase (FAAH) for AEA and monoacylglycerol lipase (MGL) for 2-AG. Inhibition of endocannabinoid metabolism is a potential approach for drug development, and there is a need for the identification of novel compounds with inhibitory effects upon FAAH and MGL.

In Paper I of this thesis, the expression of CB1 receptors in human Achilles tendon was examined. We found expression of CB1 receptors in tenocytes, blood vessel wall as well as in the perineurium of the nerve. A semi-quantitative analysis showed an increase of CB1 receptors in painful human Achilles tendinosis.

In papers II and III, termination of AEA signalling was investigated via inhibition of FAAH. In Paper II, Flu-AM1, an analogue of flurbiprofen, was investigated. The compound inhibited both FAAH and the oxygenation of 2-AG by cyclooxygenase-2. In Paper III the antifungal compound ketoconazole was shown to inhibit the cellular uptake of AEA in HepG2, CaCo-2 and C6 cell lines in a manner consistent with inhibition of FAAH.

The role of FAAH in gating the cellular accumulation of AEA was investigated in Paper IV. FAAH has been shown to control the concentration gradient of AEA across the plasmamembrane in RBL2H3 cells, whereas no such effect is seen in other FAAH-expressing cell lines. To determine whether this effect is assay dependent or due to intrinsic differences between the cell lines, we assayed four cell lines with different levels of FAAH expression using the same methodology. We found that the sensitivity of FAAH uptake inhibition was not dependent on the expression level of FAAH, suggesting that factors other than FAAH are important for uptake.

Paper V is focused on the inhibition of MGL. Prior to this study no selective inhibitors of the enzyme had been described. Thus, we screened a number of compounds for their inhibitory effect on MGL. Troglitazone was found to be an inhibitor of MGL, although its potency was dependent upon the enzyme assay used.

The endocannabinoid ligand anandamide (AEA) is removed from the extracellular space by a process ofcellular uptake followed by metabolism. In many cells, such as the RBL-2H3 cell line, inhibition of FAAH activity reduces theobserved uptake, indicating that the enzyme regulates uptake by controlling the intra- : extracellular AEA concentrationgradient. However, in other FAAH-expressing cells, no such effect is seen. It is not clear, however, whether these differencesare methodological in nature or due to properties of the cells themselves. In consequence, we have reinvestigated the roleof FAAH in gating the uptake of AEA.Methodology/Principal Findings: The effects of FAAH inhibition upon AEA uptake were investigated in four cell lines: AT1rat prostate cancer, RBL-2H3 rat basophilic leukaemia, rat C6 glioma and mouse P19 embryonic carcinoma cells. SemiquantitativePCR for the cells and for a rat brain lysate confirmed the expression of FAAH. No obvious expression of atranscript with the expected molecular weight of FLAT was seen. FAAH expression differed between cells, but all four couldaccumulate AEA in a manner inhibitable by the selective FAAH inhibitor URB597. However, there was a difference in thesensitivities seen in the reduction of uptake for a given degree of FAAH inhibition produced by a reversible FAAH inhibitor,with C6 cells being more sensitive than RBL-2H3 cells, despite rather similar expression levels and activities of FAAH. Thefour cell lines all expressed FABP5, and AEA uptake was reduced in the presence of the FABP5 inhibitor SB-FI-26, suggestingthat the different sensitivities to FAAH inhibition for C6 and RBL2H3 cells is not due to differences at the level of FABP-5.Conclusions/Significance: When assayed using the same methodology, different FAAH-expressing cells display differentsensitivities of uptake to FAAH inhibition.

Background: The endogenous cannabinoid system is involved in the control of pain. However, little is known as to the integrity of the cannabinoid system in human pain syndromes. Here we investigate the expression of the cannabinoid receptor 1 (CB(1)) in human Achilles tendons from healthy volunteers and from patients with Achilles tendinosis.

Principal Findings: CB(1)IR was seen as a granular pattern in the tenocytes. CB(1)IR was also observed in the blood vessel wall and in the perineurium of the nerve. Quantification of the immunoreactivity in tenocytes showed an increase of CB(1) receptor expression in tendinosis tissue compared to control tissue.

Conclusion: Expression of cannabinoid receptor 1 is increased in human Achilles tendinosis suggesting that the cannabinoid system may be dysregulated in this disorder.

Background: The antifungal compound ketoconazole has, in addition to its ability to interfere with fungal ergosterol synthesis, effects upon other enzymes including human CYP3A4, CYP17, lipoxygenase and thromboxane synthetase. In the present study, we have investigated whether ketoconazole affects the cellular uptake and hydrolysis of the endogenous cannabinoid receptor ligand anandamide (AEA). Methodology/Principal Findings: The effects of ketoconazole upon endocannabinoid uptake were investigated using HepG2, CaCo2, PC-3 and C6 cell lines. Fatty acid amide hydrolase (FAAH) activity was measured in HepG2 cell lysates and in intact C6 cells. Ketoconazole inhibited the uptake of AEA by HepG2 cells and CaCo2 cells with IC50 values of 17 and 18 mu M, respectively. In contrast, it had modest effects upon AEA uptake in PC-3 cells, which have a low expression of FAAH. In cell-free HepG2 lysates, ketoconazole inhibited FAAH activity with an IC50 value (for the inhibitable component) of 34 mu M. Conclusions/Significance: The present study indicates that ketoconazole can inhibit the cellular uptake of AEA at pharmacologically relevant concentrations, primarily due to its effects upon FAAH. Ketoconazole may be useful as a template for the design of dual-action FAAH/CYP17 inhibitors as a novel strategy for the treatment of prostate cancer.

BACKGROUND AND PURPOSE: Drugs used clinically usually have a primary mechanism of action, but additional effects on other biological targets can contribute to their effects. A potentially useful additional target is the endocannabinoid metabolizing enzyme monoacylglycerol lipase (MGL). We have screened a range of drugs for inhibition of MGL and compared the observed potencies using different MGL enzyme assays.

KEY RESULTS: Among the 96 compounds screened in the NPA assay, troglitazone, CP55,940, N-arachidonoyl dopamine and AM404 inhibited NPA hydrolysis by the lysates with IC(50) values of 1.1, 4.9, 0.78 and 3.1µM, respectively. The potency for troglitazone is in the same range as its primary pharmacological activity, activation of peroxisome proliferator-activated receptor (PPAR) γ. Among PPARγ ligands, the potency order towards human MGL was troglitazone > ciglitazone > rosiglitazone > 15-deoxy-Δ(12,14) -prostaglandin J(2) ≈ CAY 10415 > CAY 10514. In contrast to the time-dependent inhibitor JZL184, the potency of troglitazone was dependent upon the enzyme assay system used. Thus, troglitazone inhibited rat cytosolic 2-oleoylglycerol hydrolysis less potently (IC(50) 41µM) than hydrolysis of NPA by the human MGL lysates.

CONCLUSIONS AND IMPLICATIONS: 'Hits' in screening programmes for MGL inhibitors should be assessed in different MGL assays. Troglitazone may be a useful lead for the design of novel, dual action MGL inhibitors/PPARγ activators.

The brain is a major target site in acute cyanide intoxication, as indicated by several symptoms and signs. Cyanide inhibits the enzyme cytochrome oxidase. This inhibition causes impaired oxygen utilization in all cells affected, severe metabolic acidosis and inhibited production of energy. In this thesis, some neurotoxic effects of cyanide, in particular, the effects on dopaminergic pathways were studied.

In a previous study, decreased levels of striatal dopamine and HVA were found after severe cyanide intoxication (5-20 mg/kg i.p.). However, increased striatal dopamine were found in rats showing convulsions after infusion of low doses of cyanide (0.9 mg/kg i.v.), at the optimal dose rate (the dose rate that gives the treshold dose).

Increased striatal dopamine synthesis was observed in rats after cyanide treatment and in vitro. Furthermore, in rat, as well as in pig striatal tissue, cyanide dose- dependently increased the oxidative deamination of 5-HT (MAO-A) and DA (MAO-A and -B) but not that of PEA (MAO-B). Thus cyanide affects both the synthesis and metabolism of dopamine.

In rats, sodium cyanide (2.0 mg/kg, i.p.) decreased the striatal dopamine Dj- and D2-receptor binding 1 hour after injection. Increased extracellular levels of striatal dopamine and homovanillic acid were also shown after cyanide (2.0 mg/kg; i.p.). DOPAC and 5-HIAA were slightly decreased. This indicates an increased release or an extracellular leakage of dopamine due to neuronal damage caused by cyanide. Thus the effects of cyanide on dopamine Dj- and D2~receptors could in part be due to cyanide-induced release of dopamine.

Because of reported changes in intracellular calcium in cyanide-treated animals, the effects of cyanide on inositol phospholipid breakdown was studied. Cyanide seemed not to affect the inositol phospholipid breakdown in vitro.

The effects of cyanide on the synthesis and metabolism of brain GAB A were also examined. A decreased activity of both GAD and GAB A-T were found in the rat brain tissue. The reduced activity of GAB A-T, but not that of GAD returned to the control value after adding PLP in the incubation media. The cyanide-produced reduction of GABA levels will increase the susceptibility to convulsions, and could partly be due to GAD inhibition.

In conclusion, cyanide affects the central nervous system in a complex manner. Some effects are probably direct. The main part, however, appears to be secondary, e.g. hypoxia, seizures, changes in calcium levels or transmitter release produced by cyanide.

Cobalamin and folate are especially important for women of childbearing age due to their ubiquitous role in fetal growth and development. Population-based data on cobalamin and folate status are lacking from Nepal, where diets are mostly vegetarian. The objectives of the study were to investigate cobalamin and folate intake and status, and to explore associations with socio-demographics, anthropometrics, anemia, and dietary habits. Following a random selection of geographical clusters, we collected blood samples from 500 non-pregnant women and 24-h dietary recalls and food frequency questionnaires from a subsample of 379 women. Twenty percent of the women did not consume any food containing cobalamin during the days recalled, and in 72% nutritional cobalamin intake was <1 mu g/day. Eighty-four percent of the women had cobalamin intake lower than the estimated average requirement (EAR) (< 2 mu g/day). In contrast, only 12% of the women had a folate intake less than 100 mu g per day, whereas 62% had intake between 100 and 320 mu g. Low plasma cobalamin (< 150 pmol/L) was found in 42% of the women, most of whom (88%) also had elevated levels of methylmalonic acid. Our results indicated a high prevalence of nutritional cobalamin deficiency, while folate deficiency was uncommon.

In the light of findings indicating that cannabinoids can affect the proliferation of a number of cancer cell types and that cannabinoid receptor expression is higher in prostate cancer cell lines than in non-malignant cells, we investigated whether the level of cannabinoid 1 receptor immunoreactivity (CB(1)IR) in prostate cancer tissues is associated with disease severity and outcome. Formalin-fixed paraffin-embedded non-malignant and tumour tissue samples from patients who were diagnosed with prostate cancer at a transurethral resection for voiding problems were used. CB(1)IR, which was scored in a total of 399 cases, was associated with the epithelial cell membranes, with little staining in the stroma. Patients with a tumour CB(1)IR score greater or equal to the median (2) had a significantly higher proportion of Gleason scores 8-10, metastases at diagnosis, tumour size and rate of cell proliferation at diagnosis than patients with a score<2. For 269 cases, tumour CB(1)IR was measured for patients who only received palliative therapy at the end stages of the disease, allowing the influence of CB(1)IR upon the disease outcome to be determined. Receiver operating characteristic (ROC) curves showed an area under the curve of 0.67 (95% confidence limits 0.59-0.74) for CB(1)IR in the tumour. CB(1)IR in non-malignant tissue was not associated with disease outcome. A tumour CB(1)IR score >or=2 was associated with a significantly lower disease specific survival. A Cox proportional hazards regression indicated that the tumour CB(1)IR score and the Gleason score were independent prognostic variables. It is concluded that a high tumour CB(1)IR score is associated with prostate cancer severity and outcome.

Inhibitors of the metabolism of the endogenous cannabinoid ligand anandamide by fatty acid amide hydrolase (FAAH) reduce the gastric damage produced by non-steroidal anti-inflammatory agents and synergise with them in experimental pain models. This motivates the design of compounds with joint FAAH/cyclooxygenase (COX) inhibitory activity. Here we present data on the N-(3-methylpyridin-2-yl) amide derivatives of flurbiprofen and naproxen (Flu-AM1 and Nap-AM1, respectively) with respect to their properties towards these two enzymes. Flu-AM1 and Nap-AM1 inhibited FAAH-catalysed hydrolysis of [H-3]anandamide by rat brain homogenates with IC50 values of 044 and 0.74 mu M. The corresponding values for flurbiprofen and naproxen were 29 and > 100 mu M, respectively. The inhibition by Flu-AM1 was reversible, mixed-type, with K-slope(i) and K-intercept(i) values of 0.21 and 1.4 mu M, respectively. Flurbiprofen and Flu-AM1 both inhibited COX in the same manner with the order of potencies COX-2 vs. 2-arachidonoylglycerol > COX-1 vs. arachidonic acid > COX-2 vs. arachidonic acid with flurbiprofen being approximately 2-3 fold more potent than Flu-AM 1 in the assays. Nap-AM1 was a less potent inhibitor of COX. Flu-AM1 at low micromolar concentrations inhibited the FAAH-driven uptake of [H-3]anandamide into RBL2H3 basophilic leukaemia cells in vitro, but did not penetrate the brain in vivo sufficiently to block the binding of [F-18]DOPP to brain FAAH. It is concluded that Flu-AM 1 is a dual-action inhibitor of FAAH and COX that may be useful in exploring the optimal balance of effects on these two enzyme systems in producing peripheral alleviation of pain and inflammation in experimental models.

Background: It has been reported that direct activation of the cannabinoid CB1 receptor in epidermal growth factor (EGR)-stimulated PC-3 prostate cancer cells results in an anti-proliferative effect accompanied by a down-regulation of EGF receptors (EGFR). In the present study, we investigated whether similar effects are seen following inhibition of the endocannabinoid hydrolytic enzyme monoacylglycerol lipase (MGL).

Results: CB1 receptor expression levels were found to differ greatly between two experimental series conducted using PC-3 cells. The monoacylglycerol lipase inhibitor JZL184 increased levels of 2-arachidonoylglycerol in the PC-3 cells without producing changes in the levels of anandamide and related N-acylethanolamines. In the first series of experiments, JZL184 produced a small mitogenic effect for cells that had not been treated with EGF, whereas an anti-proliferative effect was seen for EGF-treated cells. An anti-proliferative effect for the EGF-treated cells was also seen with the CB receptor agonist CP55,940. In the second batch of cells, there was an interaction between JZL184 and CB1 receptor expression densities in linear regression analyses with EGFR expression as the dependent variable.

Conclusions: Inhibition of MGL by JZL184 can affect EGFR expression. However, the use in our hands of PC-3 cells as a model to investigate the therapeutic potential of MGL inhibitors and related compounds is compromised by their variability of CB1 receptor expression.

Background: In prostate cancer, tumour expression of cannabinoid CB1 receptors is associated with a poor prognosis. One explanation for this association comes from experiments with transfected astrocytoma cells, where a high CB receptor expression recruits the Akt signalling survival pathway. In the present study, we have investigated the association between CB1 receptor expression and the Akt pathway in a well-characterised prostate cancer tissue microarray.

Methodology/Principal Findings: Phosphorylated Akt immunoreactivity (pAkt-IR) scores were available in the database. CB1 receptor immunoreactivity (CB1IR) was rescored from previously published data using the same scale as pAkt-IR. There was a highly significant correlation between CB1IR and pAkt-IR. Further, cases with high expression levels of both biomarkers were much more likely to have a more severe form of the disease at diagnosis than those with low expression levels. The two biomarkers had additive effects, rather than an interaction, upon disease-specific survival.

Conclusions/Significance: The present study provides data that is consistent with the hypothesis that at a high CB1 receptor expression, the Akt signalling pathway becomes operative.

The two endocannabinoids, anandamide (AEA) and 2-arachidonoylglycerol (2-AG), play independent and nonredundant roles in the body. This makes the development of both selective and dual inhibitors of their inactivation an important priority. In this work we report a new series of inhibitors of monoacylglycerol lipase (MAGL) and fatty acid amide hydrolase (FAAH). Among them, (+/-)-oxiran-2-ylmethyl 6-(1,1'-biphenyl-4-yl)hexanoate (8) and (2R)-(-)-oxiran-2-ylmethyl(4-benzylphenyl)acetate (30) stand out as potent inhibitors of human recombinant MAGL (IC(50) (8) = 4.1 mu M; IC(50) (30) = 2.4 mu M), rat brain monoacylglycerol hydrolysis (IC(50) (8) = 1.8 mu M; IC(50) (30) = 0.68 mu M), and rat brain FAAH (IC(50) (8) = 5.1 mu M; IC(50) (30) = 0.29 mu M). Importantly, and in contrast to the other previously described MAGL inhibitors, these compounds behave as reversible inhibitors either of competitive (8) or noncompetitive nature (30). Hence, they could be useful to explore the therapeutic potential of reversible MAGL inhibitors.

The acetylator phenotype was determined in 59 patients with classical, seropositive and erosive rheumatoid arthritis (RA) treated with sodium-aurothiomalate or d-penicillamine. Patients with adverse drug reactions (ADR) leading to drug withdrawal (n=29) were compared with a group of patients without ADR (n=30). The frequency of slow acetylators was significantly (p< 0.05) increased in all RA patients, irrespective of the presence of ADR, particularly in the male patients, compared with a control population. No association was found between acetylator phenotype and clinical data or secondary Sjögrens's syndrome (SS).

Compounds blocking the uptake of the endogenous cannabinoid anandamide (AEA) have been used to explore the functions of the endogenous cannabinoid system in the CNS both in vivo and in vitro. In this study, the effects of four commonly used acyl-based uptake inhibitors [N-(4-hydroxyphenyl)arachidonylamide (AM404), N-(4-hydroxy-2-methylphenyl) arachidonoyl amide (VDM11), (5Z,8Z,11Z,14Z)-N-(3-furanylmethyl)-5,8,11,14-eicosatetraenamide (UCM707) and (9Z)-N-[1-((R)-4-hydroxybenzyl)-2-hydroxyethyl]-9-octadecen-amide (OMDM2)] and the related compound arvanil on C6 glioma cell viability were investigated. All five compounds reduced the ability of the cells to accumulate calcein, reduced the total nucleic acid content and increased the activity of lactate dehydrogenase recovered in the cell medium. AM404 (10 microm) and VDM11 (10 microm) acted rapidly, reducing cell viability after 3 h of exposure when cell densities of 5,000 per well were used. In contrast, UCM707 (30 microm), OMDM2 (10 microm) and the related compound arvanil (10 microm) produced a more slowly developing effect on cell viability, although robust effects were seen after 6-9 h of exposure. At higher cell densities, the toxicities of AM404 and UCM707 were reduced. Comparison of the compounds with arachidonic acid, arachidonic acid methyl ester, AEA, arachidonoyl glycine and oleic acid suggested that the toxicity of the arachidonoyl-based compounds was related primarily to the acyl side-chain rather than the head group. A variety of pre-treatments blocking possible metabolic pathways and receptor targets were tested, but the only consistent protective treatment against the effects of these compounds was the antioxidant N-acetyl-L-cysteine. It is concluded that AM404, VDM11, UCM707 and OMDM2 produce a rapid loss of C6 glioma cell viability over the same concentration range as is required for the inhibition of AEA uptake in vitro, albeit with a longer latency. Such effects should be kept in mind when acyl-derived compounds are used to probe the function of the endocannabinoid system in the CNS, particularly in chronic administration protocols.

Aims: To investigate the local antinociceptive effect as well as the possible mechanisms of action of a novel analogue of palmitoylethanolamide (PEA) N-(4-methoxy-2-nitrophenyl)hexadecanamide (HD) in the rat formalin test.

Main methods: The formalin test was used to assess the antinociceptive activity of HD in vivo. The hydrolysis of anandamide catalyzed by fatty acid amide hydrolase (FAAH) was used to determine the action of HD on FAAH activity in vitro.

Significance: HD local administration produces antinociception that probably results from an indirect activation of peripheral CB1 and CB2 cannabinoid receptors. Data suggest that 5-HT1 and opioid receptors also participate in the antinociceptive effect of this compound. HD may have potential as analgesic drug.

Objective: The discovery of a posture-dependent effect on the difference between intraocular pressure (IOP) and intracranial pressure (ICP) at the level of lamina cribrosa could have important implications for understanding glaucoma and idiopathic intracranial hypertension and could help explain visual impairments in astronauts exposed to microgravity. The aim of this study was to determine the postural influence on the difference between simultaneously measured ICP and IOP.

Methods: Eleven healthy adult volunteers (age = 46 ± 10 years) were investigated with simultaneous ICP, assessed through lumbar puncture, and IOP measurements when supine, sitting, and in 9° head-down tilt (HDT). The trans–lamina cribrosa pressure difference (TLCPD) was calculated as the difference between the IOP and ICP. To estimate the pressures at the lamina cribrosa, geometrical distances were estimated from magnetic resonance imaging and used to adjust for hydrostatic effects.

Results: The TLCPD (in millimeters of mercury) between IOP and ICP was 12.3 ± 2.2 for supine, 19.8 ± 4.6 for sitting, and 6.6 ± 2.5 for HDT. The expected 24-hour average TLCPD on earth—assuming 8 hours supine and 16 hours upright—was estimated to be 17.3mmHg. By removing the hydrostatic effects on pressure, a corresponding 24-hour average TLCPD in microgravity environment was simulated to be 6.7mmHg.

Interpretation: We provide a possible physiological explanation for how microgravity can cause symptoms similar to those seen in patients with elevated ICP. The observed posture dependency of TLCPD also implies that assessment of the difference between IOP and ICP in upright position may offer new understanding of the pathophysiology of idiopathic intracranial hypertension and glaucoma.

The objectives of this study were to explore pharmacy students’ perceptions and experiences of three-dimensional virtual worlds (3DVWs) as an instructional tool for clinical pharmacy teaching. Semi-structured interviews were carried out with Master of Science in Pharmacy students who had participated in communicative exercises in a 3DVW. Interviews were digitally recorded, transcribed and analyzed using thematic analysis. More than half of the students were positive to using 3DVWs for educational purposes and see the advantages of having a setting where communication can be practiced in an authentic but ‘safe’ environment available online. However, many students also reported technical difficulties in using the 3DVW which impacted negatively on the learning experience. Perceived ease of use and usefulness of 3DVWs appears to play an important role for students. The students’ level of engagement relates to not only their computer skills, but also to the value they place on 3DVWs as an instructional tool.